Bio-Diesel Blending System

ABSTRACT

The present application provides a bio-diesel blending system for blending a flow of a bio-diesel fuel with a flow of a second fuel. The bio-diesel blending system may include one or more second fuel skids with the flow of the second fuel, a bio-diesel tank with the flow of the bio-diesel fuel, a bio-diesel skid in communication with the bio-diesel tank, and one or more blending lines in communication with the bio-diesel skid and the second fuel skids for in-line blending of the flow of the bio-diesel fuel and the flow of the second fuel to form a blended flow.

TECHNICAL FIELD

The present application and resultant patent relates generally to gas turbine engines and more particularly relate to an in-line bio-diesel blending system that creates any desired blend of bio-diesel with other fuels without the use of a mixing tank so as to promote fuel flexibility.

BACKGROUND OF THE INVENTION

Heavy duty gas turbine engines may operate on a number of different fuels. Power plants thus may have gas turbine engines with multiple fuel capacity and may operate on, for example, diesel or natural gas. The specific fuel in use may be chosen depending upon availability, price, and other operational parameters. Moreover, there is an increased interest in renewable sources of fuel such as “bio-fuel” or “bio-diesel” fuel. Bio-fuels and diesel fuels, however, generally must be premixed before combustion. The fuels may be premixed in a number of different techniques that provide little flexibility in altering the specific proportions of the bio-diesel fuel to the diesel fuel. Moreover, a large mixing tank may be required for each proportion or blend of the fuels to be used.

There is thus a desire for systems and methods for the accurate preparation and delivery of bio-diesel fuels and blends thereof to a gas turbine engine. Such systems and methods may provide fuel flexibility for the gas turbine engine to operate on multiple fuels and any type of blend thereof.

SUMMARY OF THE INVENTION

The present application and the resultant patent thus provide a bio-diesel blending system for blending a flow of a bio-diesel fuel with a flow of a second fuel. The bio-diesel blending system may include one or more second fuel skids with the flow of the second fuel therein, a bio-diesel tank with the flow of the bio-diesel fuel therein, a bio-diesel skid in communication with the bio-diesel tank, and one or more blending lines in communication with the bio-diesel skid and the second fuel skids for in-line blending of the flow of the bio-diesel fuel and the flow of the second fuel to form a blended fuel flow.

The present application and the resultant patent further provide a method of in-line blending of a flow of bio-diesel and a flow of distillate. The method may include the steps of flowing the distillate along a diesel skid, storing the bio-diesel in a bio-diesel tank, flowing the bio-diesel through a blending line, in-line blending the bio-diesel and the distillate into a blended fuel, and flowing the blended fuel towards a combustor.

The present application and the resultant patent further provide a bio-diesel blending system for blending a flow of a bio-diesel with a flow of a distillate. The bio-diesel blending system may include a diesel fuel skid with the flow of the distillate therein, a bio-diesel tank with the flow of the bio-diesel therein, a bio-diesel skid in communication with the bio-diesel tank, and a blending line in communication with the bio-diesel skid and the distillate skid for in-line blending of the flow of the bio-diesel and the flow of the distillate to form a blended flow.

These and other features and improvements of the present application and the resultant patent will become apparent to one of ordinary skill in the art upon review of the following detailed description when taken in conjunction with the several drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a gas turbine engine showing a compressor, a combustor, a turbine, and a load.

FIG. 2 is a schematic diagram of a number of distillate skids that may be used with the gas turbine engine of FIG. 1.

FIG. 3 is a schematic diagram of a bio-diesel blending system as may be described herein.

FIG. 4 is a schematic diagram of an alternative embodiment of a bio-diesel blending system as may be described herein.

DETAILED DESCRIPTION

Referring now to the drawings, in which like numerals refer to like elements throughout the several views, FIG. 1 shows a schematic view of gas turbine engine 10 as may be used herein. The gas turbine engine 10 may include a compressor 15. The compressor 15 compresses an incoming flow of air 20. The compressor 15 delivers the compressed flow of air 20 to a combustor 25. The combustor 25 mixes the compressed flow of air 20 with a pressurized flow of fuel 30 and ignites the mixture to create a flow of combustion gases 35. Although only a single combustor 25 is shown, the gas turbine engine 10 may include any number of combustors 25. The flow of combustion gases 35 is in turn delivered to a turbine 40. The flow of combustion gases 35 drives the turbine 40 so as to produce mechanical work. The mechanical work produced in the turbine 40 drives the compressor 15 via a shaft 45 and an external load 45 such as an electrical generator and the like.

The gas turbine engine 10 may use natural gas, various types of syngas, liquid fuels, and/or other types of fuels and blends thereof. The gas turbine engine 10 may be any one of a number of different gas turbine engines offered by General Electric Company of Schenectady, N.Y., including, but not limited to, those such as a 7 or a 9 series heavy duty gas turbine engine and the like. The gas turbine engine 10 may have different configurations and may use other types of components. Other types of gas turbine engines also may be used herein. Multiple gas turbine engines, other types of turbines, and other types of power generation equipment also may be used herein together.

FIG. 2 is a schematic diagram of a conventional diesel skid 50 that may be used with the gas turbine engine 10. In this example, a first diesel skid 52 and a second diesel skid 54 are shown, although any number of the diesel skids 50 may be used. Each diesel skid 50 may be in communication with a diesel tank 55 via a distillate line 56. The diesel tank 55 may have any size, shape, or configuration. Any number of the diesel tanks 55 may be used. A diesel fuel such as a No. 2 distillate 60 may be positioned therein. Other types of fuels may be used herein.

Each diesel skid 50 may include a distillate pump 65. The distillate pump 65 may be a centrifugal pump and the like. The distillate pump 65 may have any size or capacity. A distillate heater 70 may be positioned downstream of the distillate pump 65. The distillate heater 70 may be of sufficient size and capacity to maintain the flow of distillate 60 above about fifty degrees Fahrenheit (about ten degrees Celsius) or so as to prevent filter clogging and the like. A pressure regulator 75 may be positioned downstream of the distillate heater 70. The pressure regulator 75 may have any size or capacity.

The diesel skid 50 may include a number of filters downstream of the pressure regulator 75. In this example, a self-cleaning filter 80 and a low pressure filter 85 may be used. The self-cleaning filter 80 may be a metallic filter and the like. The low pressure filter 85 may be a synthetic cartridge filter and the like. The filters 80, 85 may have any size, shape, or capacity. Other types of filtering devices may be used herein. A high pressure pump 90 may be positioned downstream of the filters 80, 85. The high pressure pump 90 may be a screw pump and the like. The high pressure pump 90 may have any size or capacity. A flow divider 92 may be positioned downstream of the high pressure pump 90. The flow divider 92 may divide the flow of distillate 60 to the various combustors 25 of the gas turbine engine 10 and the like. A number of bypass valves and stop valves also may be used herein. A recirculation line 94 may extend from the gas turbine engine 10 back to the distillate tank 55. Likewise, a waste drain tank 96 also may be used. The diesel skid 50 described herein is for the purpose of example only. Many other types of diesel skids and components may be used.

In use, a flow of distillate 60 may be pumped by the distillate pump 65 and heated to at least about fifty degrees Fahrenheit (about ten degrees Celsius) or so by the distillate heater 70. The flow of distillate 60 may be cleaned in the filters 80, 85 and pumped by high pressure pump 90 to the flow divider 92 and on to the combustors 25 of the gas turbine engine 10 for combustion therein. The flow of distillate 60 may be returned to the distillate tank 55 when the diesel skid 50 is not in use via the recirculation line 94 so as to prevent coking and the like. Other components and other configurations also may be used herein.

FIG. 3 shows a schematic diagram of a bio-diesel blending system 100 as may be described herein. The bio-diesel blending system 100 may be used with a number of the diesel skids 50 similar to those described above or otherwise. The bio-diesel blending system 100 may be used instead of a conventional blending or mixing tank as is described above.

The bio-diesel blending system 100 may include a bio-diesel tank 110. The bio-diesel tank 110 may have any size, shape, or configuration. The bio-diesel tank 110 may include a volume of a bio-diesel fuel 120 therein. The bio-diesel fuel 120 may be a bio-diesel fuel such as a B100 fuel (one hundred percent bio-diesel) and the like. The bio-diesel fuel 120 may be mixed with a number of additives 130. The additives 130 may include a biocide, a cold flow improver, and the like. A tank heater 140 may be positioned adjacent to the bio-diesel tank 110. The tank heater 140 may have a sufficient size and capacity to maintain the bio-diesel fuel 120 at about at least fifty degrees Fahrenheit (about ten degrees Celsius) or so to prevent clogging of the piping.

The bio-diesel blending system 100 may include a bio-diesel heater 150 downstream of the bio-diesel tank 110. The bio-diesel heater 150 may have any suitable size or capacity. The bio-diesel heater 150 may further warm the flow of bio-diesel fuel 120 to about sixty degrees Fahrenheit (about 15.6 degrees Celsius) for improved flowability. A number of self-cleaning filters 160 may be positioned downstream of the bio-diesel heater 150. The self-cleaning filters 160 may be a pair of metallic filters and the like. Other types of filtering devices may be used herein. A number of positive displacement pumps 170 may be positioned downstream of the self-cleaning filters 160. The positive displacement pumps 170 may have any size or capacity. In this example, three fifty-percent positive displacement pumps 170 are shown although other types of pumping devices may be used herein. Other components and other configurations may be used herein.

The bio-diesel heater 150, the self-cleaning filters 160, and the positive displacement pumps 170 have positioned on a bio-diesel skid 180 or elsewhere. The bio-diesel skid 180 may be of any size, shape, or configuration. The bio-diesel skid 180 may be positioned adjacent to the bio-diesel tank 110 or elsewhere. The bio-diesel skid may be fixed or mobile.

The bio-diesel blending system 100 may include a number of blending lines 190. A separate blending line 190 may be used for each of the diesel skid 50. Given such, a first blending line 200 and a second blending line 210 are shown. Any number of blending lines 190 may be used herein. The blending lines 190 may extend from the bio-diesel skid 180 to a T-joint 220 or another type of a flow divider. Each blending line 190 then may continue to one of the diesel skids 50 at an in-line joint 225. In this example, the blending lines 190 may tie in at the in-line joint 225 upstream of the low pressure filters 85. Other types of tie in points may be used.

Each blending line 190 may have one or more control valve 230 thereon. The control valve 230 may be in communication with a bio-diesel recirculation line 240. The bio-diesel recirculation line 240 may extend from the control valve 230 back to the bio-diesel heater 150 or elsewhere. The bio-diesel 120 may be recirculated through the bio-diesel heater 150 to prevent gelling. The control valve 230 may be a conventional three-way valve and the like. Each blending line 190 also may include a multiport drain valve 250 thereon. The multiport drain valve 250 may be positioned about a drain line 260. The drain line 260 may be in communication with the waste drain tank 96 and the like. A flow meter 270 also may be positioned on each blending line 190. The flow meter 270 may be of conventional design.

A purge line 280 may extend from the diesel skid 50 to the bio-diesel blending system 100 in order to purge the system with distillate when not in use. The bio-diesel blending system 100 may be purged with distillate when not in operation so as to reduce the energy required to maintain the bio-fuel above its gelling temperature. Other components and other configurations may be used herein.

In use, the bio-diesel blending system 100 permits the in-line blending of any percentage of the bio-diesel fuel 120 with the distillate 60 without the use of a blending tank. Specifically, the bio-diesel heater 150 may heat the bio-diesel fuel 120 to a temperature well above its pour point. The self-cleaning filter 160 may remove impurities from the bio-diesel fuel 120. The bio-diesel pumps 170 then may pump the bio-diesel fuel 120 at a desired flow rate and at the desired pressure through the blending lines 190 into the main flow of the distillate 60 at the in-line joint 225 to form a blended fuel 290. The control valves 230 may only allow the required flow rate based on input on the mainstream flow rate and/or the total flow rate as well as feedback from the bio-diesel flow meters 270. The remaining bio-diesel 120 flow may be recirculated to the bio-diesel heater 150 or elsewhere. The blended fuel 290 may have any percentage of the bio-diesel 120 therein such a B20, B30, and the like.

The bio-diesel blending system 100 thus provides the blended fuel 280 with any percentage of bio-diesel fuel 120. The blend ratio may be varied almost instantaneously. Moreover, the bio-diesel blending system 100 controls the overall injection rate and blend therein. The bio-diesel blending system 100 thus avoids the cost of a conventional blending tank or mixing chamber while providing accurate fuel blends. The use of the bio-diesel blending system 100 further permits the creation of bio-diesel blends while also allowing the gas turbine engine to operate on a flow of the distillate and/or on a flow of natural gas. The bio-diesel blending system 100 thus provides further fuel flexibility in a highly efficient system.

FIG. 4 shows a further embodiment of a bio-diesel blending system 300 as may be described herein. In this example, the bio-diesel blending system 300 may tie into the diesel skids 50 directly downstream of the bio-diesel heater 150 and the distillate heater 70 or elsewhere. Instead of using the bio-diesel pumps 170, an eductor 310 may be used for the pumping action via an eductor line 320. The eductor 310 is a mechanical device without any moving parts. Instead, the eductor 310 mixes two fluid streams based upon a momentum transfer between a motive fluid and a suction fluid. A motive inlet may be in communication with the flow of distillate 60 under pressure. The eductor 310 also may include a suction inlet. The suction inlet may be in communication with the flow of bio-diesel 120. The flow of fuel distillate 60 thus may be the motive fluid that provides suction for the flow of bio-diesel 120. The flow of distillate 60 enters the motive inlet as the motive flow and is reduced in pressure below that of the flow of bio-diesel 120 as the suction flow is accelerated therewith. The flows are mixed in the eductor 310 and exit the blended fuel 290. Although other types of mixers, mixing pumps, and the like may be used as the eductor 310. The use of the eductor 310 further simplifies the system 300 with the elimination of the pumps and like. Other components and other configurations also may be used herein.

It should be apparent that the foregoing relates only to certain embodiments of the present application and the resultant patent. Numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the invention as defined by the following claims and the equivalents thereof. 

We claim:
 1. A bio-diesel blending system for blending a flow of a bio-diesel fuel with a flow of a second fuel, comprising: one or more second fuel skids with the flow of the second fuel; a bio-diesel tank with the flow of the bio-diesel fuel; a bio-diesel skid in communication with the bio-diesel tank; and one or more blending lines in communication with the bio-diesel skid and the one or more second fuel skids for in-line blending of the flow of the bio-diesel fuel and the flow of the second fuel to form a blended flow.
 2. The bio-diesel blending system of claim 1, wherein the second fuel comprises a distillate.
 3. The bio-diesel blending system of claim 1, wherein the bio-diesel tank comprises a tank heater.
 4. The bio-diesel blending system of claim 1, wherein bio-diesel skid comprises a bio-diesel heater.
 5. The bio-diesel blending system of claim 1, wherein the bio-diesel skid comprises a filter.
 6. The bio-diesel blending system of claim 5, wherein the filter comprises one or more self-cleaning filters.
 7. The bio-diesel blending system of claim 1, wherein the bio-diesel skid comprises a pump.
 8. The bio-diesel blending system of claim 7, wherein the pump comprises one or more positive displacement pumps.
 9. The bio-diesel blending system of claim 1, wherein the one or more blending lines comprises a control valve thereon.
 10. The bio-diesel blending system of claim 9, wherein the control valve is in communication with a recirculation line.
 11. The bio-diesel blending system of claim 1, wherein the one or more blending lines comprises a flow meter thereon.
 12. The bio-diesel blending system of claim 1, wherein the one or more blending lines are in communication with the one or more second fuel skids at an in-line joint.
 13. The bio-diesel blending system of claim 12, wherein the one or more second fuel skids comprise a pump downstream of the in-line joint.
 14. The bio-diesel blending system of claim 12, wherein the one or more blending lines comprise an eductor.
 15. A method of in-line blending a flow of bio-diesel and a flow of distillate, comprising: flowing the distillate along a diesel skid; storing the bio-diesel in a bio-diesel tank; flowing the bio-diesel through a blending line; in-line blending the bio-diesel and the distillate into a blended fuel; and flowing the blended fuel to a combustor.
 16. A bio-diesel blending system for blending a flow of a bio-diesel with a flow of a distillate, comprising: a diesel fuel skid with the flow of the distillate; a bio-diesel tank with the flow of the bio-diesel; a bio-diesel skid in communication with the bio-diesel tank; and a blending line in communication with the bio-diesel skid and the distillate skid for in-line blending of the flow of the bio-diesel and the flow of the distillate into a blended flow.
 17. The bio-diesel blending system of claim 16, wherein the bio-diesel tank comprises a tank heater.
 18. The bio-diesel blending system of claim 16, wherein bio-diesel skid comprises a bio-diesel heater.
 19. The bio-diesel blending system of claim 16, wherein the bio-diesel skid comprises one or more self-cleaning filters.
 20. The bio-diesel blending system of claim 16, wherein the blending line comprises an in-line joint or an eductor. 